<p>A press-in coupling arrangement including a cast socket (16) that comprises a first frustro-conical internal surface (18) and a second frustro-conical internal surface (20). The first frustro-conical internal surface (18) has a draft angle 'A'. The draft angle 'A' may be 2 degrees or more, but preferably the draft angle 'A' will be in the range from 2 to 5 degrees. The draft angle 'B' may be 2 degrees or less. Generally, it is preferably that the internal surface having the lesser draft angle is disposed between the opening (24) of the socket (16) and the internal surface having the greater draft angle. A circumferential sloped surface (22) is formed at the opening (24) of the socket (16). The first and second internal surfaces (18, 20) each have a surface finish Ra value of about 3.2. Such a value is achievable without the need for post-cast machining due to the draft angles on the inner cast surfaces.</p>
